Headlight



C. H. ALLEN.

HEADLIGHT.

APPLICATION mm JULY 29. 1920.

Patented 0m 18, 1921.

UNITED STATES PATENT OFFICE.

CHARLES H. ALLEN, OF CHICAGO, ILLINOIS.

HEADLIGHT.

To all wit-0m it may concern:

Be it known that I, CHARLES H. ALLEN, a citizen of the United States,and a resident of the city of Chicago, in the county of Cook and Stateof Illinois, have invented certain new and useful Improvements in Headlights; and I do hereby declare that the fol lowing is a full, clear,and exact description of the same, reference being had to theaccompanying drawings, and to the numerals of reference marked thereon,which form a part of this specification.

My invention relates more particularly to a headlight for vehicles,boats or the like, in which highly polished reflecting surfaces and alens may be utilized to direct the rays of light so that most of themmay be projected horizontally below a certain horizontal plane and someof which may be directed divergently downward.

It is therefore an object of my invention to utilize a lens having aportion with parallel faces and a plano-concave portion.

It is a further object of my invention to provide reflecting surfaceswhereby the rays of light are largely directed in horizontal planes tothe lens.

It is broadly an object of my invention to construct a headlight inwhich the rays of light are confined below a certain horizontal plane.

It is also broadly an object of my invention to divide the rays into ahorizontal portion and a downwardly divergent portion.

The structure and relation of parts whereby I attain these objects arewithin the scope of my invention.

My invention in a preferred form is illustrated in the accompanyingdrawings and hereinafter more specifically described and claimed.

On the drawings:

Figure 1 is a central sectional view of a headlight embodying theprinciples of my invention.

Fig. 2 is a front face view of one of the reflecting surfaces.

Fig. 8 is a plan view of the lens showing the plain surface andplano-concave surface.

Fig. 4 is a section on the line 44 of Fig. 3.

As shown on the drawings:

In the drawings, in which similar reference numerals refer to similarfeatures in the different views, I have illustrated a head Specificationof Letters Patent.

Patented Oct. 18, 1921.

1920. Serial No. 399,736.

light in which I employ means to direct the rays of light so that themajor portion thereof will be confined below such an elevation as may beconsistent with a city ordinance or other laws, and while I haveillustrated the said means in certain relations, it is to be understoodthat the same may be varied or adjusted to suit the exigencies of aparticular case. Accordingly, I have shown a headlight structurecomprising the circular and parabolic shaped hood or container 1 havinga frontal opening in which the lens 2 may be secured in any approvedmanner. In the present instance, I employ a frame 3 resting upon ashoulder 4: provided in the front face of the hood 1. The frame 3 ispreferably provided with a groove in which the outer circumferentialpart of the lens 2 is designed to fit. The upper half of the lens 2 isprovided with a. plain portion 5 having parallel sides, while the otherhalf consists of. a plano-concave portion 6 with the concave portionfaced inwardly. The rays of light which are horizontal or are normal tothe plain portion 5 are not refracted, but pass on in horizontal planes,while practically all the luminous rays passing through theplano-concave portion are refracted in divergent directions, mostlydownwardly, since the plano-concave portion represents the lower half ofa concave disk, as shown in Fig. 3.

The light or luminous ray producing device preferably consists of anincandescent lamp 7 supported by a block 8 arranged in the lower cornerof the hood or housing 1. A reflector 9 of substantially paraboliccontour is secured to this block so as to encom' pass the lamp 8, thereflector 9 consisting of some material having a highly polishedinterior surface, like a mirror, which it may constitute. The lamp 7 isso placed in the reflector 9 that most of the rays striking theparabolic walls of the reflector 9 are reflected in lines which areparallel to the major or longitudinal axis of the reflector. In the rearend of the hood, I mount a second reflector 10 upon a bracket 11 securedto the wall of the hood 1 by any wellknown method. The reflector 10 isof such a size and shape as to receive practically all the raysreflected from the reflector 9, and preferably consists of a plainmirror or similar substance having a highly polished reflecting surface.This reflector 10 is arranged obliquely at an to a horizontal plane,which angle .is equal to the angle made with said reflector 10 by aluminous ray parallel to the longitudinal axis of the reflector 9.Therefore, the reflected rays from the parabolic reflector which areparallel to its axis are reflected from the reflector 10 in a horizontalline. The most or at least a dominating portion of the luminous rays arereflected horizontally from the reflector 10 and pass through the lens2; those striking the plain portion 5 continue in horizontal lines,while those striking the concave portion Gare refracted and diverge,principally downwardly, whereby the road and contour thereof may be seenand watched.

In Fig. 11 have diagrammatically illustrated a pair of luminous rays a;and b, which are parallel with the axis of the reflector 9.- These raysare reflected in horizontal lines from the reflector 10 since the angleof incidence is equal to the angle of reflection, ray 6 passingunrefracted through the plain medium 5, and ray a passing through theconcave portion 6 and being refracted downwardly and emerging in adownwardly divergent direction. The luminous rays passing through theplain portion 5 are designed ,to light the way straight ahead, and theirhighest point should be within the elevation demanded by the cityordinance, if such there be. It should be particularly noted that byhaving the upper half of the lens composed of plain parallel surfaces, Iavoid the upward divergence so common in lamp lenses now in use andwhich produce an objectionable height in the pencil of light emergingfrom the lens; the slight fringe which may be produced by upwardlyinclined rays emerging from the lens portion 5 can be disregarded sincethe same must be negligibly small and insignificant, if apparent at all,since most of the rays are reflected from the reflector 10 in horizontallines, or lines normal to the front face, and of the remaining rays thelarger percentage are inclined downwardly.

It will accordingly be observed that I have devised a novel headlight inwhich the upper divergence of luminous rays is eliminated in whichreflectors have been utilized to the greatest possible advantage, inwhich the pencil of rays has a lower divergent and downwardly directedportion and a horizontal directed portion creating such a distributionof light which does not require the constant tipping or shifting of theheadlight.

I am aware that numerous details of construction may be varied through awide range without departing from the principles of this invention, andI therefore do not purpose limiting the patent granted otherwise thannecessitated by the prior art.

I claim as my invention:

A headlight comprising a casing a luminous ray produc'ng device securedin the forward part of said casing and including real-wardly, aparabolic reflector surrounding said device, an inclined reflectorsecured to the rear wall of said casing for remixing the rays from saidparabolic reflector and reflecting them forward in horizontal planes,and a lens secured in the forward end of said casing, said lenscomprising an upper plain portion and a lower planoconcave portionwhereby the upper pencil of light is directed in horizontal planes andthe lower pencils of light are directed downwardly and laterally.

In testimony whereof I have hereunto subscribed my name in the presenceof two subscribing witnesses.

CHARLES H. ALLEN. Vitnesses CARLTON HILL,

SPENCER V. GIBBS.

